JP2015533759A - Decorative glass panel having a reflective layer deposited on a surface structured substrate - Google Patents

Abstract

The present invention relates to a transparent substrate (2) and a transparent layer (at least part of the surface of which is structured, a typical surface structure has a dimension of 10 nm to 100 μm, and is covered with a reflective layer (4)). 3) and a composite material (1).

Description

  The present invention relates to a decorative glazing material, wherein at least a part of the surface of the decorative glazing material is surface-structured and directly coated with a reflective layer.

  An object of the present invention is a decorated interior / exterior furniture element having a first outer (front) surface and a second (rear) surface, the first outer (front) surface being smooth and easy The second (rear) surface has a surface structure of a selected geometric shape and is provided with a reflective coating; It is to make available decorative interior / exterior furniture elements that create the decorative appearance seen on the first side of these furniture elements. They can be glass or plastic sheets or panes, or they can be elaborate and transparent glass-ceramic plates, which are interior and exterior furnishings (kitchen sideboards, furniture, etc.), household appliances Can be used for etc.

  So far, the surface structure / reflective layer set is limited by the scale and shape of the readily available surface structure, ie by the surface structuring process. In the case of those obtained by hot rolling, the scale is larger than a few hundred microns, and in the case of satin finished glass, the shape and scale of the surface structure (period 150 μm) is determined by the mechanism of chemical attack on the glass (eg attack 10 μm height depending on time).

  We are a composite material made from a sheet with a surface that can be a relatively wide non-limiting dimension on the order of 1 square meter or more, the outer surface of which is composed of a sheet of glass or the like, And the objective was to produce a composite material whose appearance is given by a fully controllable 10 nm to 100 μm surface structure that is coated with a reflective layer and covers at least part of the surface of the composite material. When the reflective layer is metallized, a controllable and reproducible surface structure allows the glazing material to have a complex appearance comparable to that of stainless steel or brushed or rubbed aluminum. . Accordingly, a table or other furniture item having a decorative effect, a wall covering tile or the like is manufactured.

As a result, this objective is
A transparent substrate,
A transparent layer, wherein at least a part of its surface is structured, the characteristic dimension of the surface structure shape is between 10 nm and 100 μm, and is coated with a reflective layer;
This has been achieved by the present invention, which is directed to a composite material continuously containing.

  Accordingly, the present invention utilizes state-of-the-art techniques for forming surface structure shapes on deformable layers, which will be described in detail later. This technique makes it possible to form embossed patterns with fully defined shapes and dimensions as large as 10 nm and larger. Thus, the structured surface of the transparent layer is regular or irregular as required, or is a complete replica of any “mother surface”, regardless of the material. In this way, the appearance of the surface of the material or a desired decorative effect is recognized when viewed from the opposite side of the transparent substrate to the transparent layer.

According to another preferred feature of the composite material of the present invention,
The characteristic dimension of the surface structure shape is at most equal to 30 μm and, in order of increasing preference, at least equal to 50, 100 and 500 nm. For example, a pattern having a depth of 1 to 2 [mu] m and a pitch of 10 to 20 [mu] m can be drawn on stainless steel and brushed or rubbed aluminum.
Transparent substrates include glass materials (borosilicate glass, heat strengthened soda lime float glass, etc. if desired), glass ceramics, especially transparent, (transparent) polymer materials such as single polycarbonate, polymethyl ( Selected from ionomer resins, such as (meth) acrylate, polystyrene, poly (vinyl chloride), polyamide, polyethylene or polypropylene, or a mixture or copolymer of a plurality of these, and for polymer materials it is the opposite of said transparent layer The side surface can be provided with an anti-scratch coating made, for example, of polysiloxane or the like.
The surface structured layer is made from a thermally crosslinkable material, in particular a sol-gel material. The advantage of this material is that it provides a layer with a high inorganic content that can withstand the process of tempering the glass plate (which constitutes the substrate) and is made of single silica, titanium oxide, zinc oxide or oxide. Aluminum or a mixture of a plurality of these may be mentioned. Silica sol is advantageously obtained by hydrolysis of a sol-gel precursor, preferably methylethoxysilane. It is important to control the preparation conditions of the sol-gel solution so that the layer remains deformable during processing.
The surface structured layer is made from a material that can be cross-linked under ultraviolet light.
The surface structured layer has a thermoplastic polymer matrix and is a single poly (methyl methacrylate), polystyrene, polycarbonate, poly (vinyl chloride), polyamide, polyethylene or polypropylene, or a mixture of several of these. Or a copolymer can be mentioned.
・ The reflective layer
・ Opaque or ・ Transparent
Including a metal, for example silver or aluminum, and / or an oxide with a high refractive index, for example TiO ₂ or ZrO ₂ , and / or a paint, when implemented according to the invention, the reflective layer is on one side Can be a plastic film that has been surface-structured, metallized, or painted and provided with an adhesive layer on the other side for adhesion to a transparent substrate;
The real refractive index at a wavelength of 600 nm is at least equal to 1.8.
The reflective layer is covered with a protective layer, the latter may be opaque or transparent, for example composed of organic and / or inorganic paints.
A part of the surface of the transparent layer is not surface structured and is covered with a reflective layer, so in this alternative form the mirror function coexists with the decorative function which is the subject of the present invention.

  The composite material can be manufactured according to several methods.

The first method is
Depositing a deformable layer, i.e. a precursor of said transparent layer, on which at least part of the surface is surface structured, onto a transparent substrate,
Contacting this deformable layer with the structured surface of the secondary stamp,
Placing the coated substrate and the secondary stamp in a bag made of an impermeable material;
Put the bag and its contents in a sealed chamber;
Evacuating air from the chamber to a pressure equal to at most 0.5 bar;
Re-introducing air into the chamber after sealing the bag,
Put the sealed bag and its contents into the autoclave,
Applying a pressure between 0.5 bar and 8 bar and a temperature of 25 ° C. and 400 ° C. for 15 minutes to several hours;
Opening the bag, then
・ Separating the base material and the secondary stamp,
including.

  Surface structure shapes formed by this method have dimensions between 10 nm and 100 μm (valley depth, protrusion height, protrusion width / diameter, valley width, etc.) and values up to several centimeters. (10 μm × 10 μm × 4 cm “wall”).

  The surface structure shape can be formed by this method on the surface of at least about 1 square meter and at most “Full Width Float” (FWT) glass plate dimensions, ie up to 3 m × 6 m.

  The method for depositing the deformable layer on the transparent substrate is not limited. Adhesion by a liquid route (thin layer coating, spray coating, dip coating, and spin coating) is employed. In thin layer application, at rest, the liquid precursor of the deformable layer forms a meniscus that hangs down from the slot, and the slot is displaced from the slot to a lateral position so that the liquid precursor is removed from the slot. Pulled out.

  The secondary stamp is so called because it is obtained as a result of molding the material against the master. The surface structuring material can be a polymer.

  The bag material is air impermeable.

  The chamber air is exhausted to a pressure equal to at most 0.5 bar, or in order of increasing preference, to 5 mbar, 2 mbar and 1 mbar. For example, the chamber air is exhausted for 15 minutes until a pressure of about 0.5 mbar is reached. After the bag is sealed, air is reintroduced into the chamber.

  Subsequently, the sealed bag is placed in an autoclave. The autoclave allows the application of pressures between 0.5 and 8 bar, and temperatures of 25 and 400 ° C. The treatment in the autoclave can be carried out for a time between 15 minutes and several hours. These parameters must be adjusted depending on the nature of the deformable layer. The purpose here is to press the secondary stamp on the deformable layer, i.e. the sol-gel or others, while cross-linking it to make it undeformable. In this way, the pattern engraved on the surface of the secondary stamp is engraved and fixed on the layer applied to the substrate surface. The sealing and evacuation steps are necessary to allow the transfer of pressure from the fluid to the stamp.

At the outlet of the autoclave, a hole is opened, the bag is opened, and the secondary stamp is pulled away from the substrate surface. The layer can then be subjected to a new heat treatment to densify and crystallize (TiO ₂ , ZnO) to improve its mechanical properties and / or change its surface hydrophilicity / hydrophobicity be able to.

  This method does not require any special equipment (system for placing under bags and autoclaves). It is used in the glass industry, in particular for laminating windshields, or also for industrial glazing materials, for example of the type of liquid crystal built-in laminated glazing of the type sold by Saint-Gobain Glass under the registered trade name of Privateite ™. It is also compatible with widely used devices for manufacturing materials.

  As long as the method only requires equipment items already deployed on the industrial line, this method would be industrially easy to operate and would be suitable for processing large glazing materials.

  This method is suitable for using low cost stamps, such as surface structured polymer sheets (especially manufactured by roll-to-roll technology). As long as the stamp is not destroyed during processing, it can be reused several times.

  The structured surface of the secondary stamp is advantageously air permeable. In this case, the contact operation during the sealing phase does not require special precautions to prevent trapping air bubbles between the coated substrate and the stamp. The stamp can be composed of an elastomeric polymer (PDMS, EVA, epoxy type) or a glassy polymer or copolymer.

  In a preferred alternative of this method, the structured surface of the secondary stamp is made of a polymer or a composite organic (polymer) / inorganic material and the temperature in the autoclave is continuously raised above the glass transition temperature of this polymer material. And then lower temperature or vice versa. This process makes it possible to precisely control the mechanical behavior of the stamp and optimize the contact between the stamp and the coated substrate and the replication quality of the structure.

  According to the second method, the transparent layer is surface-structured by using a rotating part as described in FR-A-2893610 (for example by a roll-to-plate method). .

  Formation of the reflective layer on the surface structured (transparent) layer is preferably carried out by a liquid route or a cathode sputtering route.

  The invention is illustrated by the following examples with reference to the accompanying single drawing schematically showing a composite material according to the invention.

1 schematically shows a composite material according to the invention.

  The duplication of the rubbed aluminum surface on the sol-gel silica layer will be described. This surface structure is defined by a depth of 1-2 μm and a pitch of 10-20 μm.

  A silica sol is prepared from a methyltriethoxysilane (sold by Sigma-Aldrich) / acetic acid (Prolabo) mixture with a weight ratio of 45/55. The solution is left stirring at ambient temperature for 12 hours.

  Starting from the above rubbed aluminum surface, a PDMS stamp is produced by molding. Molding was performed by casting a 10: 1 mixture of two components (elastomer: catalyst) of Sylgard (TM) 184 Silicone Elastomer Kit sold by Dow Corning, removing residual bubbles under vacuum, and then removing the elastomer to 80 By crosslinking at 4 ° C. for 4 hours.

The sol is applied by spin coating (2000 rpm, 1 minute) onto a 10 × 10 cm ² 2 mm glass substrate sold by Saint-Gobain Glass under the trade name Planilux ™. The surface of the glass substrate is previously cleaned with a Cerox ™ abrasive. The layer is dried at 50 ° C. for 5 minutes.

  Following deposition, the structured surface of the PDMS stamp is contacted with a sol-gel silica layer. To eliminate air bubbles that can impair contact between the layer and the mask, the sample is placed in a sealing bag and placed in a sealed chamber that is evacuated until a vacuum of 0.5 mbar is reached. After 20 minutes, the bag is sealed by thermal bonding.

  Subsequently, the samples are placed in an autoclave, where they simultaneously undergo a temperature rise to 110 ° C. and a pressure rise to 1.75 bar (5 ° C. for 5 minutes, 60 ° C. over 5 minutes, 60 ° C. for 10 minutes). Hold up to 110 ° C. over 5 minutes, hold at 110 ° C. for 20 minutes, drop to 35 ° C. over 15 minutes, rise from 0 bar to 1.75 bar over 5 minutes, hold 40 minutes at 1.75 bar, over 15 minutes Descent to 0 bar). Once removed from the autoclave, the sample is removed from the mold under low temperature conditions.

  The characteristics of pattern transfer to the sol-gel silica layer are examined by AFM. The pattern obtained is the same as that of the stamp.

By this method, the same replication can be made with a thermoplastic layer, for example poly (methyl methacrylate), or a composite thermoplastic-inorganic layer, for example poly (methyl methacrylate) -SiO ₂ layer.

  Two types of reflective layers are deposited on the glass sample with the surface structured silica layer thus formed.

The first type of reflective layer has the following procedure:
-Protect the non-structured surface with an acid-resistant adhesive film,
Dilute the silver plating solution (Dr.-Ing. Schmitt GmbH (dilutable solution supplied by Dieselstr. 16, 64807 Dietburg / Germany)) by:
• 42 μl of Miraflex ™ 1200 (first liquid) in a 250 cm ³ flask
125 μl of Miraflex ™ PD (second liquid) in a 250 cm ³ flask
6 ml of Miraflex ™ RV (third liquid) in a 250 cm ³ flask
6 ml of Miraflex ™ S (fourth liquid) in a 250 cm ³ flask
-Put the glass substrate into a tank and pour the contents of the first liquid (directly on the glass) into it (including Sn ²⁺ ions and Sn ⁴⁺ ions),
Stir for 1 minute and then rinse with distilled water
-Put the glass substrate into the second tank and pour the contents of the second liquid (directly on the glass) into it (including Pd ²⁺ ions),
Stir for 1 minute and then rinse with distilled water
Place the glass substrate in the final tank and pour the contents of the third and fourth liquid (not directly on the glass) into it (after the start of the stopwatch) (including silver nitrate and reducing agent),
Stir for 30 seconds, then rinse with distilled water,
-Put the glass substrate in the first tank and stir for 1 minute.
・ Rinse with distilled water.
A silver layer deposited according to the procedure.

  The silver layer thus produced has a thickness of about 80 nm.

A second type of reflective layer is formed on a structured surface of silica by magnetron cathode sputtering using a TiO ₂ target, a 30% Ar / (Ar + O ₂ ) gas mixture, and a deposition pressure of 2 × 10 ⁻³ mbar. A TiO ₂ layer deposited in the same manner as the silver layer.

The silver or TiO ₂ layer is then coated with a layer of about 50 μm thickness, which is sprayed with Fenzi brand alkyd type paint and baked at 180 ° C. for 15 minutes.

  Referring to the attached single drawing, a composite material 1 composed of a continuous glass plate 2, a surface structured silica layer 3, a reflective layer 4 and a protective layer 5 was thus obtained. Although the surface structured silica layer 3 and the reflective layer 4 are paired from the free surface side of the glass plate 2, the surface structure of the rubbing treated aluminum can be seen. With the present invention any surface structure and any corresponding decorative appearance can be obtained.

Claims (15)

A transparent substrate (2),
A transparent layer (3), wherein at least part of its surface is structured, the characteristic dimension of the surface structure shape is between 10 nm and 100 μm, and is covered with a reflective layer (4) Layer (3);
A composite material (1) comprising   2. Composite material (1) according to claim 1, characterized in that the characteristic dimension of the surface structure shape is at most equal to 30 [mu] m.   3. Composite material (1) according to claim 1 or 2, characterized in that the characteristic dimension of the surface structure shape is at least equal to 50 nm.   4. Composite material (1) according to one of claims 1 to 3, characterized in that the characteristic dimension of the surface structure shape is at least equal to 100 nm.   5. Composite material (1) according to one of claims 1 to 4, characterized in that the characteristic dimension of the surface structure shape is at least equal to 500 nm.   6. Composite material (1) according to one of claims 1 to 5, characterized in that the transparent substrate (2) is selected from glass materials, glass ceramics and polymer materials.   7. Composite material (1) according to one of claims 1 to 6, characterized in that the surface structured layer (3) is made from a heat-crosslinkable material.   7. Composite material (1) according to one of claims 1 to 6, characterized in that the surface-structured layer (3) is made of a material that can be cross-linked under ultraviolet light. ).   7. Composite material (1) according to one of claims 1 to 6, characterized in that the surface structured layer (3) has a thermoplastic polymer matrix.   10. Composite material (1) according to one of claims 1 to 9, characterized in that the reflective layer (4) is opaque.   10. Composite material (1) according to any one of claims 1 to 9, characterized in that the reflective layer (4) is transparent. The reflective layer (4) comprises a metal, for example silver or aluminum, and / or an oxide with a high refractive index, for example TiO ₂ or ZrO ₂ , and / or a paint. 12. The composite material (1) according to 1 above.   13. Composite material (1) according to one of the preceding claims, characterized in that the reflective layer (4) has a real refractive index at a wavelength of 600 nm equal to at least 1.8.   14. Composite material (1) according to one of claims 1 to 13, characterized in that the reflective layer (4) is coated with a protective layer (5).   15. Composite material according to one of claims 1 to 14, characterized in that part of the surface of the transparent layer (3) is unstructured and is covered with a reflective layer (4). 1).